Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
Photo by Tomoyuki Kusenose
「脱炭素時代の住宅密集地における自然密接型住宅の一例」
(English Below)
この建物は、紫外線の増加や気温上昇を引き起こしている地球温暖化の時代に、本州で最も年間の曇り日（雨の日を含む）が多く、また冬には気温低下するため積雪量が多く雪国ともされる北陸地方を敷地とした、脱炭素時代の住宅密集地における自然密接型住宅の一例である。
最も特徴的な点は、一極集中した採光窓から吹抜けを通して建物全体で太陽光の採光を共有することで、建物外皮の熱損失の原因となる採光窓の面積を建物全体で大きく減らしている点である。施工を担当した住宅メーカーの一般的な採光計画を行った類似規模の実例と比較した結果、「A＝(採光窓面積)/(延べ床面積)」、「B＝(採光窓面積)/(外皮面積)」、とした時に、本計画のA、Bは、類似規模のA、Bそれぞれの平均値の0.67倍及び0.61倍という数値が得られ、採光窓面積を2／3程度に留められていることが分かった。
一般住宅では稀な３層吹抜けの最上部に建物全体の採光窓を集中的に配置することで一般的な住宅にある窓際より明るい窓際が生まれ、光の明暗対比が強調された非日常的な縦長空間を住宅内に作り出した。また採光窓の一極集中は光の指向性を高め、壁素材や床、家具等の凹凸による陰影のコントラストを高め、３層吹抜けの音の響き効果とともに、屋内空間の立体感や奥行きを強調し、まるで屋外のような吹抜け空間を演出している。
２階個室においては、吹抜け側の壁面を全面ガラスにし、太陽光を外壁側でなく屋内吹抜け側でとることで、熱損失を抑えつつも開放的な採光窓を実現した。屋内の採光窓を簡素な納まりで透明感を感じさせる木製建具で製作したことで、明るい吹抜け空間と一体的な個室空間が生まれた。
春や秋の中間期は建物最上部の換気窓、各個室の窓や１階ソファーコーナーの換気窓からかなりの量の風が吹抜けを吹き抜ける。比較的小さな空間が、明るさだけでなく風と音で、よりいっそう屋外的な空気へと変化する。
夏は吹抜け空間における気圧換気により余計な熱を排出するほか、駐車場コンクリート土間への散水気化熱による冷気の取り込みを可能としている。
冬は吹抜けに多量の太陽光を取り込むことで温室効果を得て、シーリングファンの空気循環により１階から最上階までの建物内全体の空気を温めることができる。
建物最上部に太陽光の動きを取り込める水平に連続したアルミサッシガラス面を設け、アルミ製の横型ブラインドの角度調整により、その面から入る太陽光による明るさを建主が生活に合わせ適切に調整できる。太陽光の動きや換気窓から抜ける風の動きを感じたり、観葉植物が太陽光の下で生き生きした姿を見せる屋内空間は、自然環境が建主の生活の各場面で身体の活力や癒しにつながることにもなり、季節に関わらずまるで一年中屋内に晴れている庭を設えているような住宅となっている。
各階の天井高さや階高は１階を低く天井高2.2ｍ(階高2.7ｍ)、２階を高く天井高2.5ｍとしている。これにより１階ソファーコーナーは天井高さが2.2ｍと低い落ち着いた空間となり、ソファーコーナーから床が400mm上がったラウンジ空間は２階の廊下や個室との距離が極端に近く相互コミュニケーションの可能性を感じさせる空間となっている。また、一般的な2.5ｍの天井高さにも関わらず床面積を小さくした２階の各個室は、縦長の開放性をもち、総長6.6ｍの縦長の吹抜け砂質塗り壁がつくる光のグラデーションを効果的に切り取った開口を持った空間とした。２階廊下は上部への開放性と、下階の家族や植物との近接感を備えており、椅子を持ち出した軽作業など、機能上活用しやすい空間とした。
太陽光の動きが作る風景を最も美しく感じられるのは１階のソファーコーナーである。
天候による雲の動きや、季節と時間の経過によって変化する砂質塗り壁の縦方向の光と影のグラデーション。太陽光に向け上方向に生き生き育つ観葉植物。吹抜け上部から吊り下げられたペンダント照明とそれを吊るすまっすぐなコード。そういった、ラウンジや吹き抜けの縦方向の光の集まりを床段差で上方に上っていく水平のパノラマとして切り取ることで、縦横の各方向性が強調された美しい風景をつくりだしている。
日本人の身体にも馴染むように天井の高さが抑えられ明るさが抑えられた落ち着きのあるソファーコーナー。そこから眺める３層吹抜けの砂質壁に映し出される自然の作り出す光の大きさや動きは、薄暗い日本の伝統建築の居室から、高さが抑えられた縁側開口を通して、空から豊かな光が降り注ぐ屋外庭を眺める経験にも似ている。
このように、地球温暖化の時代に、悪天候が多く雪国でもある北陸地方で、脱炭素化を図りつつも、住宅密集地という環境下で、自然を身近に感じながら建主が心地よく生活できる住宅の一例を体現することができた。この建築が我々が直面している地球環境時代における一つの解として、少しでも多くの方の共感を得られると嬉しい。
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“An example of nature-connected housing in a dense residential area of decarbonized era“
This building is an example of nature-connected housing in a dense residential area in the era of decarbonization in the era of global warming, which is causing increased ultraviolet radiation and rising temperatures. The site is located in the Hokuriku region which has the most cloudy days (including rainy days) per year in Honshu and is also considered a snowy region with large snowfall due to lower temperatures in the winter.
The most distinctive feature of this project is that the area of daylighting windows, which cause heat loss in the building envelope, is significantly reduced throughout the building by sharing sunlight throughout the building from a centralized daylighting window and an atrium. Compared to a similarly sized building with a general lighting plan by the housing manufacturer in charge of construction, A and B are 0.67 times and 0.61 times the average values of A and B, respectively, when “A = (lighting window area)/(total floor area)” and “B = (lighting window area)/(exterior skin area)” are used. It was found that the window area was kept at about 2/3 of the average value of similar size A and B.
The centralized daylighting windows of the entire building at the top of the three-story atrium, which is rare in general housing, make the area by windows much brighter than that in general housing, creating an extraordinary vertical space in the house that emphasizes the contrast between light and dark. The concentration of the windows enhances the directionality of the light, and the contrast of shading caused by the unevenness of the wall material, floor, and furniture, as well as the sound effect of the three-story atrium, emphasizes the three-dimensionality and depth of the interior space, creating an outdoor-like atrium space.
In the second-floor private rooms, the walls on the atrium side are entirely made of glass, allowing sunlight to enter not from the exterior walls but from the interior atrium side, thereby reducing heat loss and creating an open, well-lit window. The interior lighting windows can be simply manufactured with wooden fittings that give a sense of transparency, creating a bright atrium space and an integrated private room space.
During the spring and fall mid-seasons, a considerable amount of wind blows through the atrium from the ventilation windows at the top of the building, the windows in each private room, and the ventilation windows in the sofa corner on the first floor. The relatively small space is transformed into a more open-air atmosphere not only by the brightness but also by the wind and sound.
In summer, the air pressure ventilation in the atrium space allows excess heat to be discharged and cool air to be drawn in by the evaporative heat of water sprinkled on the concrete dirt floor of the parking lot.
In winter, a large amount of sunlight is captured in the atrium to create a greenhouse effect, and the air circulation of ceiling fans warms the overall air of the building from the first floor to the top floor.
The top of the building has a continuous horizontal aluminum sash glass surface that allows sunlight to move in, and the angle of the horizontal aluminum blinds can be adjusted to allow the owner to adjust the brightness of the sunlight coming in from that surface to suit his or her lifestyle. The indoor space where one can feel the movement of sunlight and wind through the ventilation windows, and where the houseplants look alive under the sunlight, leads to a natural environment that energizes and heals the body in every aspect of the owner’s life, making the house feel as if it has a sunny garden indoors all year round, regardless of the season.
The ceiling height and floor height of each floor is set to be 2.2m (2.7m floor height) with a low ceiling on the first floor and a high ceiling of 2.5m on the second floor. This makes the sofa corner on the first floor a calm space with a low ceiling height of 2.2 m. The lounge space, with its floor raised 400 mm from the sofa corner, is extremely close to the corridor and private rooms on the second floor, creating the possibility of mutual communication. The second-floor corridor has an openness to the upper floor and a sense of proximity to the family and plants on the lower floor. The second-floor corridor is open to the upper floor and has a sense of proximity to the family and plants on the lower floor, making it a space that can easily be used for functional purposes, such as light work with a chair.
The place to enjoy the most beautiful scenery created by the movement of sunlight is the sofa corner on the first floor.
The vertical gradation of light and shadow on the sand-plastered wall changes with the course of time and seasons, as well as the movement of clouds due to weather conditions. Houseplants growing lively in the upward direction facing sunlight. Pendant lights suspended from the top of the atrium and the straight cords that hang from them. By cutting the longitudinally directed light gathering in the lounge and atrium as a horizontal panorama which rises upward at the different level of floor, it creates a beautiful landscape that emphasizes each directional aspect of length and breadth.
The sofa corner was set calm with a restrained ceiling height and reduced brightness to fit in with body of Japanese people. From there, the view of the magnitude and movement of the light created by nature reflected on the sand-plastered walls of the three-story atrium is like the experience of looking out from the dimly lit living room of a traditional Japanese building through the lowered height of the porch opening into an outdoor garden with abundant light pouring down from the sky.
In this way, in this era of global warming, we were able to embody an example of a house that allows the owner to live comfortably while feeling close to nature in a densely populated residential environment, while at the same time decarbonizing the environment in the Hokuriku region with a lot of bad weather and heavy snowfall. We hope that this architecture will resonate with as many people as possible as one of the solutions for the global environmental era we are facing.